1. Field of the Invention
The present invention relates to the general art of geometric instruments, and to the particular field of scribers used on curved surfaces.
2. Discussion of the Related Art
Pipe welders are often called upon to cut one conduit to engage a second conduit. The term xe2x80x9cconduitxe2x80x9d will be used to cover pipes, tubes and other such curved elements. At the present time, this procedure is carried out using a template. The template is formed by a template maker after the pipe welder has supplied dimensions. The template is then placed on a conduit to be cut and the conduit is cut.
This process requires the pipe fitter to wait until the template is supplied before proceeding with his work. This wait is wasteful of the pipe fitter""s time and can be costly to his employer due to the down time of the pipe fitter. The wait can be anywhere from a few minutes to hours, or even days, depending on the circumstances.
Therefore, there is a need for a means and a method for defining a cutting guide mark on a conduit which will be joined to another conduit adjacent to the cut made along the cutting guide mark without requiring use of a template.
Often, the pipe fitter is in a location that is not convenient for obtaining a template. Not only does this increase the time required to obtain a template, it also increases the difficulty in obtaining the template.
Therefore, there is a need for a means and a method for in situ defining a cutting guide mark on a conduit which will be joined to another conduit adjacent to the cut made along the cutting guide mark without requiring use of a template.
Often, templates formed for one conduit may not be as accurate and as precise as possible for another conduit. This may be caused by manufacturing tolerances or environmental conditions or the like.
Therefore, there is a need for a means and a method for defining a cutting guide mark on a conduit which will be joined to another conduit-adjacent to the cut made along the cutting guide mark without requiring use of a template yet which can accurately and precisely mark each conduit.
It is a main object of the present invention to provide a means for defining a cutting guide mark on a conduit which will be joined to another conduit adjacent to a cut made along the cutting guide mark without requiring use of a template.
It is another object of the present invention to provide an in situ means for defining a cutting guide mark on a conduit which will be joined to another conduit adjacent to a cut made along the cutting guide mark without requiring use of a template.
It is a specific object of the present invention to provide a scribe for defining a cutting guide mark on a conduit which will be joined to another conduit adjacent to a cut made along the cutting guide mark without requiring use of a template.
It is another object of the present invention to provide a means for defining a cutting guide mark on a conduit which will be joined to another conduit adjacent to a cut made along the cutting guide mark without requiring use of a template and which will accurately and precisely define the cutting guide mark.
It is another object of the present invention to provide a method for defining a cutting guide mark on a conduit which will be joined to another conduit adjacent to a cut made along the cutting guide mark without requiring use of a template.
These, and other, objects are achieved by a conduit marking scribe comprising a body; a pivot unit on one end of the body, the pivot unit including a wheel which is adapted to contact the outer surface of a first conduit which will be engaged with a second conduit after the second conduit has been cut; and a scribe unit movably mounted on the body, the scribe unit including a scribe element which includes a distal end and which is movable between a first position having the distal end located inside the scribe unit and a second position having the distal end located outside the scribe unit with the distal end in position to contact the outer surface of the second conduit, and a biasing element which biases the scribe element toward the second position.
The objects are also achieved by a method of marking a conduit which includes providing the scribe unit described above, temporarily attaching one end of the second conduit to the outer surface of the first conduit at a location where the second conduit will be joined to the first conduit; contacting the wheel against the outer surface of the first conduit; contacting the wheel against the outer surface of the first conduit, contacting the wheel against the outer surface of the first conduit; locating the scribe unit against the outer surface of the second conduit; contacting the distal end of the scribe unit against the outer surface of the first conduit; and marking the second conduit by moving the scribe unit with respect to the first conduit and with respect to the second conduit so the distal end of the scribe unit engages and marks the second conduit while the wheel of the pivot unit remains in contact with the outer surface of the first conduit and moves over the outer surface of the first conduit.
The scribe will be used in place and thus the user need not wait for a template and will be able to define cutting guide marks that are accurate and precise for the particular job. In this way, if one particular job is slightly different from another, the scribe and method embodying the present invention can accommodate such difference and still provide an accurate and precise cutting guide mark. The scribe embodying the present invention is very easy to transport and thus can be available to the worker at any time and anywhere it is needed.
Still further, the scribe embodying the present invention is easily adaptable for use with additional geometric instruments, such as a ruler. However, the scribe embodying the present invention can be used by itself without requiring any additional instruments for its proper use.